Is there a compatible extension cord for earphones like this?

I want to make sure I can use the built in mic and remote. My earphones work just fine with my laptop, but I recently got a Mac Pro and I usually keep it much farther away from where I'm sitting. I noticed the plug for the earphones has four metal segments rather than three on normal ones. I presume that extra contact point is what's used for the inputs from the microphone and remote.